Learning.WekaWrapper.java Source code

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Here is the source code for Learning.WekaWrapper.java

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/*
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package Learning;

import java.util.Random;
import weka.classifiers.Evaluation;
import weka.classifiers.bayes.BayesNet;
import weka.classifiers.meta.CVParameterSelection;
import weka.classifiers.trees.J48;
import weka.core.Instances;
import weka.core.converters.ConverterUtils;
import weka.filters.Filter;
import weka.filters.unsupervised.attribute.NumericToNominal;

/**
 *
 * @author jxy
 */
public class WekaWrapper {

    J48 tree;
    Evaluation eval;

    public J48 getTree() {
        return tree;
    }

    public Evaluation getEval() {
        return eval;
    }

    public double[] evaluate(String fn) throws Exception {

        ConverterUtils.DataSource source = new ConverterUtils.DataSource(fn);

        Instances data = source.getDataSet();

        // setting class attribute if the data format does not provide this information
        // For example, the XRFF format saves the class attribute information as well
        if (data.classIndex() == -1) {
            data.setClassIndex(data.numAttributes() - 1);
        }

        NumericToNominal nmf = new NumericToNominal();
        nmf.setInputFormat(data);
        data = Filter.useFilter(data, nmf);

        tree = new J48(); // new instance of tree

        String[] options = new String[1];

        options[0] = "-C 0.25 -M 2";
        tree.setOptions(options);
        tree.buildClassifier(data); // build classifier

        // eval
        eval = new Evaluation(data);
        eval.crossValidateModel(tree, data, 5, new Random(1));

        // System.out.println("corr: " + eval.pctCorrect());
        // System.out.println("inco: " + eval.pctIncorrect());
        // System.out.println(eval.toSummaryString());
        // System.out.println(eval.toMatrixString());
        //  System.out.println(eval.toClassDetailsString());
        double[] results = new double[2];
        results[0] = eval.pctCorrect();
        results[1] = eval.pctIncorrect();
        return results;
    }

}